diff options
| author | Matthieu Sozeau | 2016-11-18 13:25:05 +0100 |
|---|---|---|
| committer | Matthieu Sozeau | 2016-11-30 11:29:02 +0100 |
| commit | 25c82d55497db43bf2cd131f10d2ef366758bbe1 (patch) | |
| tree | fdc509d76371e210aa292b49c2bf22537424b3fb /toplevel/command.ml | |
| parent | 17559d528cf7ff92a089d1b966c500424ba45099 (diff) | |
Fix UGraph.check_eq!
Universes are kept in normal form w.r.t. equality but not the <=
relation, so the previous check worked almost always but was actually
too strict! In cases like (max(Set,u) = u) when u is declared >= Set it
was failing to find an equality. Applying the KISS principle:
u = v <-> u <= v /\ v <= u.
Fix invariant breakage that triggered the discovery of the check_eq bug as well. No algebraic universes should appear in a term position (on the left of
a colon in a typing judgment), this was not the case when an algebraic
universe instantiated an evar that appeared in the term. We force their
universe variable status to change in refresh_universes to avoid this.
Fix ind sort inference: Use syntactic universe equality for inductive
sort inference instead of check_leq (which now correctly takes
constraints into account) and simplify code
Diffstat (limited to 'toplevel/command.ml')
| -rw-r--r-- | toplevel/command.ml | 8 |
1 files changed, 3 insertions, 5 deletions
diff --git a/toplevel/command.ml b/toplevel/command.ml index 7ffe680e5e..ed3eac51b6 100644 --- a/toplevel/command.ml +++ b/toplevel/command.ml @@ -537,11 +537,9 @@ let inductive_levels env evdref poly arities inds = in let duu = Sorts.univ_of_sort du in let evd = - if not (Univ.is_small_univ duu) && Evd.check_eq evd cu duu then - if is_flexible_sort evd duu then - if Evd.check_leq evd Univ.type0_univ duu then - evd - else Evd.set_eq_sort env evd (Prop Null) du + if not (Univ.is_small_univ duu) && Univ.Universe.equal cu duu then + if is_flexible_sort evd duu && not (Evd.check_leq evd Univ.type0_univ duu) then + Evd.set_eq_sort env evd (Prop Null) du else evd else Evd.set_eq_sort env evd (Type cu) du in |